This invention relates in general to a thermal transfer printer, and in particular, to a thermal transfer printer having a ribbon forwarding mechanism and a head biasing-releasing mechanism.
Thermal transfer printers are known in the art as disclosed in Japanese Patent Publication No. 21471/82. This prior art printer utilizes the driving force for moving the carriage carrying the thermal head separate to wind the ribbon. Another known thermal printer utilizes a separate motor for forwarding the ink ribbon. Typically, a solenoid plunger is utilized for biasing-releasing the thermal print head in thermal transfer printers.
These prior art mechanisms have been satisfactory; however, in the first device the carriage must move in order to use a desired color on a color ink ribbon, resulting in low speed printing. The second printer is expensive as two motors are required to drive the ink ribbon take-up and the thermal head. In both cases, noise and shock are generated by the solenoid plunger when used as the head biasing-releasing device. In view of this, noiseless printing which is desirable cannot be obtained. Additionally, where the ribbon take-up mechanism is actuated by a single driving source, the thermal head biasing-releasing driving mechanism must be controlled separately. This causes the construction of a driving control system to become complicated and results in increased costs.
Accordingly, it is desirable to provide a thermal transfer printer which overcomes the shortcomings of the prior art devices described above.